Using this Hydro Flask tumbler is easy. Just open the closeable press - in lid by sliding it wide. You can drink directly or use a reusable straw. For hot or cold drinks, simply fill it up and slide the lid shut to keep the temperature. When it comes to cleaning, you can put it in the dishwasher thanks to its Color Last™ powder coat. But to keep it in the best condition, try not to use abrasive cleaners. Also, avoid dropping it on hard surfaces as it's made of stainless steel but can still get dented. This tumbler is BPA - free and toxin - free, so you don't have to worry about any harmful substances while using it.